Can a new car be registered to 2 person even though there's only one name on the loan?

The registration will need to match the title. The lienholder has the title and the title will only be in the person's name who has the loan. The lienholder will not allow you to add someone else's name to the title unless you refinance in both names. The only way I can see that you can add the 2nd person's name is to pay off the car or refinance.

Every State has their own rules and regulations.You should check with the Division of Motor Vehicles for your state at a local DMV Agent.Usually the Loan Companies want the vehicle registered to the person that made the loan.

In the UK, a car can be only registered to one 'keeper' the 'owner' as such is NOT registered - it doesn't matter who paid for the car, the registration does not indicate OWNERSHIP. The official documentation should indicate the person most likely to have control of the vehicle, in most cases this will be the same person as the person who has paid for it, but where this is not the case, the 'keeper' of the vehicle should be the one on the documentation.

Yes it can, For instance my 1964 buick skylark is registed to both myself and my daughter. She drives it full time. the reason for this is if for any reason someone attempts to take the car (Like an Ex-husban) (Thats a while down the road yet for her though) he will not be able to sell or claim the car unless I as well sign the title over to him. It's called a Secure of asset. It also makes it possible for myself or her to pull the car from impound if that for some reason happens.